1. Field of the Invention
The present invention relates to a library apparatus and library system that accommodates recording media, writes data on the recording media, and reads data therefrom.
2. Description of the Related Art
The library system is an apparatus that is used in a data search system, etc., and accommodates numerous recording media, selects a recoding medium on which desirably accessing data is recorded from among these recording media, and gains access to the selected data.
One example of the library system is disclosed in Unexamined Japanese Patent Application KOKAI Publication No. 2000-90545. It is assumed that the contents of this document are included in this specification.
The library system described in Unexamined Japanese Patent Application KOKAI Publication No. 2000-90545 is called a modular data storage system. This library system can increase a recording medium accommodating capacity by placing one or a plurality of additional library apparatuses (additional modules) upon a basic library apparatus (basic module).
In this library system, the basic module has a transfer mechanism, and the additional modules have cabinets and read/write apparatuses but no transfer mechanism. The transfer mechanism of the basic module transfers the recording media among the cabinets of a plurality of modules and between read/write apparatuses.
According to this system structure, one transfer mechanism transfers the recording media between all cabinets of the plurality of modules and between read/write apparatuses. For this reason, the distance where the transfer mechanism reciprocates for carrying a recording media becomes long and much time is required for reciprocating motion, so that the recoding media cannot be efficiently transferred in some cases.